Abstract:
The U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) assessed the ecological condition of estuaries, bays, and tidal rivers in the Virginian Biogeographic Province (Cape Cod, Massachusetts, to Cape Henry, Virginia) during July-September 1990-1993. Indicators measured at 425 probability-based stations included
water quality (temperature, salinity, clarity, dissolved oxygen), contamination and toxicity of sediment, structure of benthic and fish communities, and gross external pathology of fishes. These data were used to quantify the condition of ecological resources in the entire province, as well as in three subgroups (small estuaries, large estuaries, major tidal rivers). Also characterized was the condition of ecological resources for four major estuarine systems within the province (Chesapeake Bay, Delaware Bay, Hudson-Raritan system, Long Island Sound) and three tidal rivers in the Chesapeake Bay watershed (Potomac, Rappahannock, James). The data provide an unbiased baseline estimate of estuarine conditions in this province in the early 1990s. They should be useful in assessing long-term and broad-scale questions such as global climate change, biodiversity, and environmental impacts.